This invention relates to battery assembly, including electrical contact arrangement for providing electrical power from a battery to a circuit board for a portable hand held computing device.
Portable hand held computing devices, such as radiotelephones, have become more compact. One of the contributing factors in providing a more compact hand held device is an advance in rechargeable battery technology, such as a lithium ion or lithium polymer battery, for transferring electrical power from the battery to a circuit board. However, a continuing objective for hand held devices is to further reduce the device form factor by maximizing efficient use of available space within the device.
In a conventional approach for rechargeable battery attachment in a hand held device, a battery pack (including battery, protection circuitry and contact terminals) is externally attached to the hand held device housing, with a battery contact pin device exposed outside the housing. The pin device includes an electrical connector on the circuit board that is mechanically biased by a spring against a battery terminal. In this approach, the spring loaded pin device and the external mounting of the battery pack become limiting factors in further reduction of the thickness of the hand held device, unless other functional and structural features of the pin device are made thinner and/or more tightly spaced on a circuit board for the hand held device.
A portable radiotelephone having a detachable battery (1702 in FIG. 17), externally mounted on a clam shell cover, is disclosed in U.S. Pat. No. 5,933,330, issued to Beutler et al. The overall thickness of the housing, as shown in FIG. 1, is about 26 mm and includes a battery height of about 7 mm. Use of conventional approaches such as these provides hand held devices with thicknesses of about 23-30 mm.
In an unusual approach implemented by Qualcomm, a battery is internally positioned, within the housing, a pin device is attached to the battery, and the circuit board provides an electrical terminal. Although this approach may reduce overall hand held device thickness to below 23 mm, this approach is also limited by pin device thickness, which is usually greater than battery thickness.
What is needed is a battery/hand held device configuration and associated device housing that permits use of smaller overall hand held device thickness, wherein the connections to the power source are reconfigured to provide an improved architecture and improved performance that allow easier device gripping and less device bulk.
These needs are met by the invention, which provides a reconfiguration of placement of the battery, within the hand held device housing. A spring-loaded pin device for battery contact is mounted on another side of a circuit board, the battery is mounted within, not external to, the device housing, and the spring-loaded pins are exposed through apertures in the circuit board for contact with terminals on a battery pack. Battery placement within the device housing allows additional reduction in thickness of the hand held device, and allows a reduction in cost and a further reduction in hand held device thickness.